Removal of methylated arsenic in groundwater with iron filings.

Field and laboratory experiments were conducted to study the potential use of Fe filings to remove monomethyl arsenate (MMA) and dimethyl arsenate (DMA) from contaminated waters. Batch experiments show that the affinity of MMAfor Fe filings is comparable to that of inorganic arsenate, but lower than that for arsenite. In contrast, very little DMA was retained by Fe filings or their corrosion products.